Thursday, October 6, 2011

Chevrolet blazer fuel pump wiring diagram?

1st the fuel pump relay will only energize for 2 seconds on key up, then wont energize again until the key is in crank position.

Jump the terminals at the fuel pump relay( look on the relay for terminal position)Listen for the pump to run, If it doesn't, go back to the tank and tap on it with a hammer to jar the pump. If it takes off and runs, Replace the pump. This is a very common symptom of a fuel pump.

Make sure the service engine soon lamp( check engine , amber lamp) comes on with the key in run. If it doesn't then cycle the key on and off 5-6 times and see if it comes on.

These vehicles have a problem with the ignition switches not making contact sometimes. The ses lamp must turn on when key is on! This lets you know the computer is working and has power.

The ECM commands the relay on for two second when the key is turned to run. It has to see engine rpm before it energizes it to run. The oil pressure sensor also puts power back to the fuel pump once oil pressure comes up.

Here is the wire diagram for the fuel pump. Make sure the ECM B fuse is good and has power

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For more car related problem troubleshooting:---

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